Rebecca Harris will be the Conservative Party's chief whip in Kemi Badenoch's new shadow cabinet.
The MP for Castle Point in Essex — who was first elected in 2010 — will replace Stuart Andrew.
The job of chief whip is to maintain party discipline and try to ensure MPs vote as the leadership would like them to.
The process of appointments will begin on Monday and the formal announcements of who will be in Kemi Badenoch’s senior team will be made on Tuesday, the BBC understands.
The new leader of the Conservatives won the party's leadership contest on Saturday and became the first black woman to lead a major political party in the UK.
In a speech after the result was announced, she hinted Robert Jenrick, who she was running against, may be offered a senior job, telling him “you have a key role in our party for years to come”.
Badenoch, who became an MP in 2017 after a career in banking and IT, has said she would offer jobs to all of the Tories who launched leadership bids in July.
But shadow home secretary James Cleverly, who came third in the race, has ruled himself out.
Stuart Andrew, who is the Tory MP for Daventry, said in a post on X that it has been “an hour and a privilege to serve as the Conservative Party Chief Whip”.
“Rebecca Harris is a great friend and a brilliant Whip,” he said. “I wish her all the best in the role.”
Harris was first elected as a Conservative MP for Castle Point in 2010 in the general election, which the Tories won under the leadership of David Cameron.
In 2022, she became the Comptroller of the Royal Household and which saw her walk in front of Queen Elizabeth II's coffin - the first woman to do so since the role began in 1399.
After the 2024 election, she was appointed as the party’s deputy chief whip.
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